Diaphragm power jack

ABSTRACT

Method for increasing the distance between two faces, inserting into a space between the two faces a diaphragm power jack, the shape of which being adapted to the shape of the space, the diaphragm power jack comprising two abutting sheets being sealingly bonded along the entire circumference, a pipe penetrating the bonded, injecting a pressurized fluid through the pipe to the interface between the two sheets thereby forcing the sheets apart whereby substantially all the energy from the pressurized fluid being converted to forces perpendicularly to the sheets.

The Present invention is related to a diaphragm power jack and a methodof utilizing same.

In numerous situations within many fields efforts have been made toincrease a distance between two parts in a quick and efficient way. Sucha situation occurs when two flanges which have been clamped together,are to be loosened. In such case one of the flanges should be moved awayfrom the other or even both flanges should be axially displaced.

In many other cases the aim is to remove or displace only one of theparts between which a gap exists. This is the case by partitioning asubject into smaller parts which is the case in stone quarries, whenremoving a concrete outer layer from a pipe, etc.

The need for a small and effective tool to provide a very strong forcein a selected direction, substantially without loss of energy in otherdirections will increase productivity and the accuracy of theperformance substantially.

In connection with repairs of pipelines of the above mentioned type aconsiderable amount of time is used for removing the outer concretelayer to give accessibility to the pipe itself for repairs maintenanceor modifications. It is in fact known to cut tracks in the concretearound the exterior circumference and likewise longitudinal cuts wherebyhydraulic tools are used to press the sections apart in a tangentialdirection, resulting in braking the concrete out in small pieces.

The forces from the tool may be released between parallel flat orcylindric sheets. The forces will be directed perpendicularly to theplane of the flat sheets or perpendicularly or radially to the cylindricplane of cylindric sheets. In the latter case the direction is radiallyinwardly from a stronger outer cylinder or radially outwardly from astronger inner cylinder, of which the first case will be a clampingoperation.

Repair of pipelines on difficult accessible places, such as at the seabed, is time consuming and in many ways very difficult if repair work isto be made by welding. A ruptured pipeline usually is cut and a newportion inserted which portion thereafter has to be welded to thepipeline at both ends.

The method and tool according to the present invention very efficientlysolve the above mentioned problem operations in the above mentionedapplication fields as well as others by concentrating the force inputalmost completely to the desired force direction, perpendicularly to thesheets, if plane or cylindric, the direction being linear or radial.

The above mentioned objectives are achieved with the method and toolaccording to the present invention as defined with the features statedin the patent claims.

In the drawing

FIG. 1 in a cross sectional way schematically discloses the toolaccording to the present invention before use and

FIG. 2 discloses the same tool after use, in an expanded position,

FIG. 3 discloses the tool in FIGS. 1 and 2 in a side view,

FIG. 4 discloses schematically the method for cutting a section of aconcrete layer around a pipe line out by means of the tool according tothe present invention,

FIG. 5 discloses the principle for removing flanges from each other bymeans of the present invention,

FIG. 6 discloses schematically in an axial section the tool according tothe present invention in the shape of a cylinder for provision of radialforces,

FIG. 7 discloses an enlargement of a detail from FIG. 6,

FIG. 8 discloses a longitudinal section through a tool for connection oftwo pipes before the operation,

FIG. 9 discloses a cross section from FIG. 10,

FIG. 10 discloses a longitudinal section corresponding with FIG. 8,however after the clamping operation,

FIG. 11 discloses rock breaking by means of the diaphragm power jackaccording to the invention and

FIG. 12 discloses an alternative method for manufacturing the planepower jack.

FIG. 4 discloses one application field for the present invention, namelypart of a pipe line 9 embedded in a concrete layer such as an oil pipearranged on a seabed. In cases where repairs, maintenance or inspectionmust be performed on the pipeline, the need to remove the concrete layeralong a portion of the pipe arises.

According to the present invention a slot 10 is worked out in theconcrete layer, along the entire circumference of the same and radiallyinwardly to the pipe 9. The concrete 7 is further cut into sections 8with longitudinal slots. In the circumferential slot 10 a power jackaccording to the present invention is inserted, the power jack therebyhaving an arcuate shape as disclosed in FIG. 3, covering exactly thecircumferential length of the section 8 selected by the longitudinalslots. The diaphragm power jack according to the invention principallycomprises two sheets 1, 2 being sealingly connected to each other alongthe circumference. The two sheets 1 and 2 have a shape corresponding tothe surfaces against which the sheets 1 and 2 are to be pressed, such asthe shape of FIG. 3 to be used in connection with the cylinder shapedisclosed in FIG. 4. The thickness of the sheets 1 and 2 correspondsubstantially width of the slot 10.

Upon inserting of the diaphragm power jack into the slot 10, hydraulicfluid is forced in between the sheets 1 and 2 through a correspondingpipe 3 protruding out from the end. Upon pressurizing, the diaphragmpower jack will assume the shape disclosed in FIG. 2 while forcing thesection 8 axially from the slot 10, the binding between concrete section8 and the pipe 9 thereby being ruptured by the shearing forces and thesection 8 being removed from the pipe 9 substantially in one part. Thesection 8 previously being cut by the circumferential slot 10 as well asaxial slots 6.

Based on the same principle two flanges 11, 12 as disclosed in FIG. 5may be pressed away from each other after loosening bolts or otherclamping devices, by inserting the diaphragm power jack according to thepresent invention in the slot between the flanges, pressurizing theinnerface between the two sheets 1 and 2 through the pipe 3 thereby torelease the flanges 11 and 12 from each other.

The tool according to the present invention provides an excellentpossibility to cut rocks from a stone quarry, tear down houses etc.instead of using for example dynamite. By means of an angle grinder asegment shaped groove is made in the rock, concrete etc. A diaphragmpower jack having the same shape as the groove thereafter is insertedinto the groove, pressurizing the jack will break up the rock orconcrete breaks into pieces of desirable seize.

FIG. 6 discloses the principle of the diaphragm power jack according tothe present invention, used in the form of a cylinder, the sheets 1 and2 both being constituted by abutting cylinders sealingly connected atboth axial ends and a pipe 3 giving admittance for pressurized fluid tothe interface between the two sheets or cylinders, as clearly can beseen from FIG. 7. By inserting the connected sheet cylinders 1 and 2into a correspondingly shaped space between two cylinder faces, thetotal force provided by the pressurized fluid may be used to widen theouter cylinder face or shrinking the inner cylinder face, depending onwhich of both has the strongest resistance.

FIGS. 8-10 disclose one embodiment of the diaphragm power jack accordingto the present invention as used to sealingly connect two substantiallyabutting pipes 13 and 14.

The diaphragm power jack according to the present invention for thispurpose comprises an inner cylinder 16 and an outer cylinder 15 beingsealingly connected at both ends such as by welding and being providedwith at least one pipe 3 (not shown in FIGS. 8-10) for the purpose ofpressurizing the power jack. The outer cylinder 15 is suitably providedwith outer strengthening flanges 17 and the inner cylinder 16 issuitably provided with inwardly protruding acute shaped cams 18 at leastalong selected portion thereof. The inner cylinder 16 furthermorecomprises outer grooves 4 along selected portions in the axialdirection, thereby partly weakening the material of the inner cylinder16, partly creating a space for receipt of redundant material from theinner cylinder 16 during the shrinkage operation.

The fluid used may be water or oil and preferably a plastic material ina liquid form when being injected through the pipe 3 under highpressure, thereafter curing and hardening to maintain or even increase apermanent high pressure from the outer cylinder 15 to the inner cylinder16 and further to the pipes 13 and 14.

In a further embodiment the diaphragm power jack according to thepresent invention also may be used to sealingly connect two pipes havingdifferent outer diameters, the outer and inner cylinders 15 and 16thereby being manufactured correspondingly and preferably comprising twoseparated interface, each having slots 4.

I claim:
 1. A device for interconnecting in a sealing manner the endportions of two substantially aligned pipes, comprisingouter and innercylindrical sleeves formed from a metal that are sealingly joinedtogether at their ends to form an intermediate, closed annular spacetherebetween to which a pressure medium may be supplied, said innersleeve forming a clamping sleeve that is subjected to shrinking when apressure medium is supplied to said closed annular space, whereby whensaid inner sleeve is under a pressure medium influence said inner sleeveis pressed into sealing contact with the abutting end portions of twosubstantially aligned pipes that are positioned within said innersleeve; a plurality of longitudinally extending groove means that areuniformly distributed over the outer surface of said inner sleeve forreceiving sleeve material that is brought to flow during shrinking ofsaid inner sleeve under a pressure medium influence, whereby said innersleeve maintains its circular cross-section as it shrinks; and aplurality of inwardly projecting, peripherally extending ribs that areprovided on the inner surface of said inner sleeve to penetrate theouter surface of two substantially aligned pipes positioned within saidinner sleeve during the shrinking of said inner sleeve under a pressuremedium influence, whereby leakage barriers are formed.
 2. A deviceaccording to claim 1, wherein both said inner and outer sleeves are madefrom steel.
 3. A device according to claim 1, wherein the pressuremedium supplied is a curable medium that, after curing, maintainspressure on said inner sleeve.
 4. A device according to claim 2, whereinthe pressure medium supplied is a curable medium that, after curing,maintains pressure on said inner sleeve.